The aim of this study is to conduct an additional analysis of the experiment in capitation reimbursement of pharmacies launched by the Iowa Medicaid program. The focus is on selected beliefs, attitudes, and behavior of the participating pharmacists and of the physicians who wrote the majority of the prescriptions filled by those pharmacists. The proposal has two intertwined objectives, both of which involve integrating already-collected prescription data with data to be obtained from semi-structured, open-ended personal interviews with the pharmacists and physicians. To our knowledge, this will be the first time this technique has been systematically used to explore the rationales of the prescribing patterns of physicians and the views of physicians on the role of the pharmacist in drug product selection. The first objective is to explore dimensions of the relationships between physicians and pharmacists which may help to account for the extreme variations found among the experimental pharmacies in rates of generic substitution of prescriptions for Medicaid patients. The second objective is to explore the rationales of physicians for aberrant or questionable prescribing patterns which may be detected as a result of a quality analysis of the prescription data.